Yes. See the Mastercard Chargeback Guide regarding dispute documentation.
The cardholder email, cardholder letter, and/or cardholder message (including through a password-protected website) must come directly from the cardholder or, in the case of a commercial card, the corporate entity. A completed Dispute Resolution Form must be the direct result of a conversation with the cardholder.
and the VISA Operating Rules
If the Dispute requires an Issuer to provide certification on behalf of the Cardholder, they may only certify if they obtained the dispute information through a secure method, for example:
Secure online banking: Any method used by the Cardholder that establishes their unique identity through use of a password and/or other login identification method is considered a valid representation of the Cardholder signature
Secure telephone banking: Where the Cardholder was identified using the same level of security needed to complete a transfer of funds to another financial institution
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